If you can build fro around 200-250k per unit, it may seem attractive, depending on time frame, debt terms, and the ability to achieve 2k per month in rent.Great product to build.

Operators that are open and able to offer combined usages for slower seasons, such as mid term discounted extended stay rates in the winter, can improve lower estimated production in the off-seasons. 

The toilets flush fine if there’s no paper products in them.

If you're slowly increasing but still slightly under market, have a better product, or better service (or all 3) and have rental comps to back it up, if they start to ask you can highlight these points. 

Look at State Employee's Credit Union (North Carolina) and check out their mortgage products.

And when demand is high, the product goes to the highest bidder.

Definitely a more niche type of product, but, incredibly useful, especially across the Midwest where many rental properties are less than 100k.

I'm a product of my environment. ;) 

There is no one best product.  

Work with a broker who has access to a large variety is going to help you find an appropriate option for your situation vs a direct lender who can only sell you their limited product set.